[Hepatitis B and C risk factors in Germany--results of the national surveillance].

Collection of risk factor data is part of the national surveillance of hepatitis B and C in Germany. After modifications of risk factor surveillance had been implemented in September 2003, the response rate for data on risk factors increased markedly. For the period between September 2003 and August 2004, information on risk factors (at least one "yes" or "no" answer) was available for 66% (1853) of all notified hepatitis B cases and for 67% (5813) of all notified hepatitis C cases. More than 30% of those hepatitis B cases occurred among risk groups for whom hepatitis B immunisation is recommended by the German Advisory Committee on Immunisation (STIKO). Of the hepatitis C cases with risk factor data, 40% reported previous or continuing injecting drug use (IDU). IDU was predominant among young men (78% among men, aged 15 to 29 years) and can explain the comparatively high incidence observed in young adults, especially among men. The impact of other risk factors (e. g. medical interventions) cannot be quantified without a proper control group. The results of this study demonstrate that--in addition to the hepatitis B immunisation of children and adolescents--vaccination coverage of specific risk groups, as defined by the STIKO, should be increased. Measures to prevent hepatitis C have to focus on intravenous drug users and clearly have to be intensified.